The Auto function on a camcorder makes it easy to get clear images at all times, but the result may not always seem quite as attractive as the images you see on TV or in a movie theater. The difference is that professionals have full control over their shooting conditions, rather than relying on an automatic function.
The manual ring accurately reflects delicate fingertip control of your video images. Once you learn to use it, you'll be quite impressed with the videos you create.